What is power?

I'm a biomechanics guy - power is work divided by time. move faster, more power. move more weight in the same time also more power. power is aggressive movement. connect your point of contact with uke to your core by being properly 'braced' (look up Stuart McGill's work on core strength) and apply your entire body mass to accelerating uke to the floor. Not so much in training, though, you want uke to not be knocked out when you throw them - in the dojo that is... Street? that's another story.

I like McGill's stuff - especially with regard to mobility work being an important consideration for stability under heavier workloads. I think a big difference in what I've seen with regard to Western approaches to explosive power is well represented when he talks about stiffening the muscles to create the natural "belt" - there's a notion there that is perpetuated in the "strong first" methodology in building strength/power whereby you have your core lifts/training, your stability work, some dynamic power training, and I'm a big fan of those results as I think they are functionally awesome and enhance a lot of life/athletic activities.

I also think a key difference is in how Eastern vs. Western methods account for creating a cohesive and connected body - how much is focused early on the subconscious management of forces via mind-directed-intent inside an individual as well as when paired off with another VS. progressive performance under stress and load. The conditioning aspects are also different - I think both aim for "whole body" approaches but Western is more straightforward explosive power and mobility and I think achievable in shorter durations of focused effort while Eastern requires more dedicated focused training on specific patterns that take longer fundamentally to wire together the bone muscle tissue, develop middle/dantien/etc. and connect them with mind-body-breath-intention in a way that creates less obvious but still whole-body "elastic" power.

By the way, not trying to claim is superior to another - just like different styles of martial arts were created with different purposes and contexts - and there's ever more and more ways to train - I'm more or less looking at the macro suites of skills and methods to develop them. The devil will be in the details and I think most important in either approach is having someone knowledgeable to help you get started, while giving feedback and brokering introductions with the right communities along the way to help you improve and progress.

Make sure to constantly develop your own power - kokyu style, while at the same time learning all the waza, and then trying to use them while neutralising uke's power, thereby making your own 'power' much more effective.